how about this question given that y=2x+4/x-2 and dy/dx=k/(x-2)^2.find the value of k

Question

anonymous · Answer

my typing sucks. let me try again 
$$f'(x)=5(3x+1)^4\times 3=15(3x+1)^4$$ by the chain rule
$$f'(-1)=15(-3+1)^4$$ whatever that is

anonymous · Answer

like this the answer?

.sam. · Answer

Well, what's 15(-3+1)^4 ?

anonymous · Answer

it looks like the function being differentiated is a rational function (the quotient of two polynomials).  If the function is actually (2x+4)/(x-2), then you would differentiate the rational function using the quotient rule.  Direct comparison would then lead to a value for k.